Baryon-number-violating nucleon decays in sterile neutrino effective field theories

TL;DR

This paper explores how sterile neutrino effective field theories can induce baryon-number-violating nucleon decays, analyzing operator bases, decay rates, and experimental constraints to shed light on physics beyond the Standard Model.

Contribution

It systematically studies BNV nucleon decays within sterile neutrino EFTs, including operator bases, decay calculations, and experimental constraints, providing new insights into BNV processes.

Findings

Derived effective chiral Lagrangian for BNV interactions.

Calculated nucleon decay rates to sterile neutrinos and SM neutrinos.

Established constraints on ultraviolet scales from Super-Kamiokande data.

Abstract

The search for baryon-number-violating (BNV) nucleon decay provides an intriguing probe of new physics beyond the Standard Model (SM). Future neutrino experiments will improve the sensitivity to BNV nucleon decays and can serve to search for dark particles. In this work, we study the sterile neutrino effective field theories (EFTs) with baryon number violation and the impact of light sterile neutrino on BNV nucleon decays. We revisit the dimension-6 and dimension-7 EFT operator bases with $|\Delta (B-L)|=2$ or $|\Delta (B-L)|=0$. They are then matched to the baryon chiral perturbation theory. We obtain the effective chiral Lagrangian at low energies and the BNV interactions between the sterile neutrino and baryons and mesons. The rates of nucleon decay to SM neutrinos or a sterile neutrino are calculated. We then show the constraints on the ultraviolet scale from nucleon decay search at Super-K. The correlation of two EFT operators and the dependence on the sterile neutrino mass are also investigated.